/Engine/Plugins/Experimental/Mutable/Source/CustomizableObjectEditor/Classes/MuCOE/Nodes/CustomizableObjectNodeSkeletalMesh.h
Check if lower UV channels pins of the same LOD and Section are also linked to a Layout Node.
bool CheckIsValidLayout ( const [UEdGraphPin](API\Runtime\Engine\EdGraph\UEdGraphPin) * Pin, int32 & LayoutIndex, [FString](API\Runtime\Core\Containers\FString) & MaterialName )